Solar radiation includes ultraviolet (UV) radiation, wavelength of which is between 200 nm and 400 nm. Exposure of skin to UV-A (320 to 400 nm) and UV-B (290 to 320 nm) causes various problems like reddening of the skin, localized irritation, sunburn, melanoma and formation of wrinkles. UV radiation is also known to cause damage to hair. Therefore, it is desirable to protect the skin and other keratinous substrates of the human body from the harmful effects of both UV-A and UV-B radiation.
SPF (Sun Protection Factor) is a measure of the protection from solar radiation. In order to achieve this, formulators generally include high amounts of UV-A and UV-B. The present inventors have found when compound of the triazine group is used without additional UVA or UVB sunscreen, when non-ionic surfactant is included in a cosmetic base comprising fatty acids, it is possible to provide high SPF.
Compounds of triazine group have been included in sunscreen compositions. WO07/144670 (Reckitt & Colman) discloses a skincare composition in the form of an emulsion comprising: a) an organic sunscreen component comprising at least one sunscreen selected from the group consisting of bis-ethylhexyloxyphenol methoxyphenyl triazine and methylene bis-benzotriazolyl tetramethylbutylphenol; b) a moisturising system comprising starch or a derivative thereof and a polymeric quaternary compound salt having humectant properties; and c) a carrier comprising an oil phase, an aqueous phase and an emulsifying system, said emulsifying system comprising at least one emulsifier selected from an anionic or non-ionic emulsifier. The composition is claimed to not only reduce the effect of UV radiation on the skin from UV damage, it also improves the moisturisation levels to help protect the skin from the effects of UV radiation.
EP1634624 (L'Oreal, 2006) discloses a cosmetic or dermatological photoprotective composition which comprises at least 1,3,5-triazine derivative (I) and arylalkyl benzoate derivative (II) to improve the factor of solar protection, cosmetic properties and/or stability of (A).
Non-ionic surfactants have been disclosed in the past for use in skin compositions. WO2008/022946 (Unilever) discloses a photostable cosmetic composition comprising 0.1 to 10% dibenzoylmethane or its derivative, 0.1 to 10% by weight p-methoxycinnamic acid or its derivative, 0.5 to 8% by weight C8 to C18 fatty alcohol ethoxylate and 0.5 to 8% polyalkyleneglycol.
The prior art does not disclose stable sunscreen compositions which comprise triazine compounds and whose sunprotection is enhanced specifically through use of non-ionic surfactants in a fatty acid containing oil-in-water emulsion.
It is thus an object of the present invention to obviate the drawbacks of the prior art and provide high SPF photo-protective sunscreen compositions.
Another object of the present invention is to achieve the above object using relatively low amounts of sunscreen agents thereby keeping costs low.